In accordance with a development of a digital technology, technologies capable of analyzing and classifying image information into specific regions or specific portions have been developed. A face recognition technology among these analyzing technologies, which is a technology integrated with a digital camera as well as an apparatus performing a security technology, or the like, has been studied and developed in a variety of ways.
In addition, a research into a system authenticating identity of an individual using biological characteristics such as a genetic signature, a fingerprint, a voice, a vein, a face shape, a pupil, an iris, or the like, has been actively carried out. Among these, a pupil recognition field is expected to be used the most in future for a security system due to advantages such as a high recognition ratio, unforgeability, pattern characteristics of a large amount of data, no changing factor, and the like.
Particularly, in order to provide a variety of convenience functions (e.g., prevention of drowsy driving, adjustment of a headlight direction based on a driver's gaze, and the like) to a driver in a vehicle, the technology for detecting the pupil of the driver even in a technology for tracking the driver's gaze is a key factor.
Since the technology for detecting the pupil according to the related art detects the driver's pupil from an image by using a fixed threshold based binarization technique without taking account of illuminance of a timing of photographing the image, there is a lack of accuracy.